As of June 25, 2025, Mexican health authorities have confirmed a troubling rise in human infections caused by the New World screwworm (Cochliomyia hominivorax), a parasitic fly whose larvae feed on living tissue. The number of confirmed human cases has climbed to 23, with 13 individuals currently hospitalized, signaling a significant public health concern in southern Mexico.
The majority of cases have been reported in the states of Chiapas and Campeche, where rural populations are more likely to come into contact with infected livestock or untreated wounds—ideal conditions for the screwworm to thrive. The parasite enters the body through open wounds, where it lays eggs that hatch into larvae, causing a condition known as *myiasis. If not treated promptly, the infestation can lead to severe tissue damage and secondary infections.
Health officials have emphasized the urgency of early detection and larval extraction, as there is no specific pharmaceutical treatment for the condition. Public awareness campaigns are underway to educate residents on wound care, animal hygiene, and the importance of seeking medical attention at the first sign of infection.
The outbreak has also affected livestock, prompting the U.S. Department of Agriculture to suspend imports of Mexican cattle and goats earlier this year. In response, Mexican and U.S. authorities are collaborating on containment strategies, including surveillance and vector control.
This resurgence of the screwworm—once eradicated in much of North America—raises concerns about environmental changes and gaps in veterinary oversight. Officials warn that without swift action, the parasite could spread further north, potentially reaching the U.S. border. The situation underscores the need for coordinated cross-border efforts to protect both human and animal health.
Source: OEM
